video capture to opc

madmat99

Hi guys, first post so i hope its in the right place. I am working on a project with 30 strips of leds controlled by 4 fadecandy boards. i have everything working and can play "video" very low res across my grid. the question is, can i add a video capture board and send the incoming video directly to my pixel map? in effect processing would just be converting video to pixel map.

any help is greatly appreciated

Regards

Matthew Tiley

jeremydouglass

Will the capture board be generating a video stream like a webcam? If so, use Capture. That can convert video to pixel map -- there are many demos and example sketches.

• https://processing.org/reference/libraries/video/Capture.html

madmat99

thats great. sorry to sound daft but where would i insert my pixel grid into this code.

attached copy of grid

// Connect to the local instance of fcserver opc = new OPC(this, "127.0.0.1", 7890);

opc.ledStrip(0, 64, width/2 , height/2 +160, width / 64.0, 0, false); opc.ledStrip(64, 64, width/2 , height/2 +150, width / 64.0, 0, false); opc.ledStrip(128, 64, width/2, height/2 +140, width / 64.0, 0, false); opc.ledStrip(192, 64, width/2, height/2 +130, width / 64.0, 0, false); opc.ledStrip(256, 64, width/2, height/2 +120, width / 64.0, 0, false); opc.ledStrip(320, 64, width/2, height/2 +110, width / 64.0, 0, false); opc.ledStrip(384, 64, width/2, height/2 +100, width / 64.0, 0, false); opc.ledStrip(448, 64, width/2, height/2 +90, width / 64.0, 0, false); opc.ledStrip(512, 64, width/2, height/2 +80, width / 64.0, 0, false); opc.ledStrip(576, 64, width/2, height/2 +70, width / 64.0, 0, false); opc.ledStrip(640, 64, width/2, height/2 +60, width / 64.0, 0, false); opc.ledStrip(704, 64, width/2, height/2 +50, width / 64.0, 0, false); opc.ledStrip(768, 64, width/2, height/2 +40, width / 64.0, 0, false); opc.ledStrip(832, 64, width/2, height/2 +30, width / 64.0, 0, false); opc.ledStrip(896, 64, width/2, height/2 +20, width / 64.0, 0, false); opc.ledStrip(960, 64, width/2, height/2 +10, width / 64.0, 0, false);
opc.ledStrip(1024, 64, width/2, height/2, width / 64.0, 0, false); opc.ledStrip(1088, 64, width/2, height/2 -10, width / 64.0, 0, false); opc.ledStrip(1152, 64, width/2, height/2 -20, width / 64.0, 0, false); opc.ledStrip(1216, 64, width/2, height/2 -30, width / 64.0, 0, false); opc.ledStrip(1280, 64, width/2, height/2 -40, width / 64.0, 0, false); opc.ledStrip(1344, 64, width/2, height/2 -50, width / 64.0, 0, false); opc.ledStrip(1408, 64, width/2, height/2 -60, width / 64.0, 0, false); opc.ledStrip(1472, 64, width/2, height/2 -70, width / 64.0, 0, false); opc.ledStrip(1536, 64, width/2, height/2 -80, width / 64.0, 0, false); opc.ledStrip(1600, 64, width/2, height/2 -90, width / 64.0, 0, false); opc.ledStrip(1664, 64, width/2, height/2 -100, width / 64.0, 0, false); opc.ledStrip(1728, 64, width/2, height/2 -110, width / 64.0, 0, false); opc.ledStrip(1792, 64, width/2, height/2 -120, width / 64.0, 0, false); opc.ledStrip(1856, 64, width/2, height/2 -130, width / 64.0, 0, false); opc.ledStrip(1920, 64, width/2, height/2 -140, width / 64.0, 0, false); opc.ledStrip(1984, 64, width/2, height/2 -150, width / 64.0, 0, false); }

jeremydouglass

I'm not sure. Where did you get this code? What does it do?

Fadecandy has simple demo sketches of sending an image out for display on their homepage:

https://github.com/scanlime/fadecandy/blob/master/doc/processing_opc_client.md

...and the capture library I already linked has simple demos of getting an image from a video stream. So, can you get an image, then send it? When you try, what happens?

Notice the key quote when reading the documentation:

When you draw to the screen, the LEDs automatically update.

madmat99

this is the code that programs the pixel map in the video sketch i have running, its running 30 strips of LEDS. i need to put this in a capture sketch so i have the same output grid but I'm not sure where to put it. is there any way i can send you the sketch i have working so you can see what i mean?

Regards

Mat

jeremydouglass

@madmat99 -- did you look at the quote and link to examples I posted above you? If you read that page, it will be clear.

Try this first:

1. Load your capture movie and define your strips in setup
2. In draw(), draw the movie image to the screen.
3. What you draw to the screen will automagically go to the LEDs.

madmat99

is this in processing 3?

jeremydouglass

Are you asking me if Fadecandy's OPC is Processing 3 compatible? I'm not sure. Have you looked at the documentation and tried it?

madmat99

sorry, I'm asking if your using processing 3 as I'm using 2 and don't seem to have the functions you mention.

jeremydouglass

Ah. Well, as it says at the top of the Capture library (the very first link I sent you): Processing 3.

You didn't say which functions, but if you need the reference for the Processing 2 Capture, you could look it up in P2, or check the way back machine:

https://web.archive.org/web/20150919131346/https://www.processing.org/reference/libraries/video/Capture.html

jeremydouglass

Hmm. Interfaces to Capture for P2 and P3 look the same. So I'm not actually sure what you mean when you say "don't seem to have the functions you mention."

madmat99

ok, here we go! this is a example sketch that came with the fadecandy software and runs fine, i adjusted the grid to fit what i have this is one running video, i copied my grid over and again runs fine i have copied the capture example in to a sketch and works fine so the question is where do i copy my grid into the capture sketch to get it running

and this is the piano with the lights running on it

(https://www.facebook.com/matthewtileydesigns/media_set?set=vb.100013160683654&type=2)

koogs

you can replace this

  opc.ledStrip(0, 64, width/2 , height/2 +160, width / 64.0, 0, false);
  opc.ledStrip(64, 64, width/2 , height/2 +150, width / 64.0, 0, false);
  opc.ledStrip(128, 64, width/2, height/2 +140, width / 64.0, 0, false);
  opc.ledStrip(192, 64, width/2, height/2 +130, width / 64.0, 0, false);
  opc.ledStrip(256, 64, width/2, height/2 +120, width / 64.0, 0, false);
  opc.ledStrip(320, 64, width/2, height/2 +110, width / 64.0, 0, false);
  opc.ledStrip(384, 64, width/2, height/2 +100, width / 64.0, 0, false);
  opc.ledStrip(448, 64, width/2, height/2 +90, width / 64.0, 0, false);
  opc.ledStrip(512, 64, width/2, height/2 +80, width / 64.0, 0, false);
  opc.ledStrip(576, 64, width/2, height/2 +70, width / 64.0, 0, false);
  opc.ledStrip(640, 64, width/2, height/2 +60, width / 64.0, 0, false);
  opc.ledStrip(704, 64, width/2, height/2 +50, width / 64.0, 0, false);
  opc.ledStrip(768, 64, width/2, height/2 +40, width / 64.0, 0, false);
  opc.ledStrip(832, 64, width/2, height/2 +30, width / 64.0, 0, false);
  opc.ledStrip(896, 64, width/2, height/2 +20, width / 64.0, 0, false);
  opc.ledStrip(960, 64, width/2, height/2 +10, width / 64.0, 0, false);       
  opc.ledStrip(1024, 64, width/2, height/2, width / 64.0, 0, false);
  opc.ledStrip(1088, 64, width/2, height/2 -10, width / 64.0, 0, false);
  opc.ledStrip(1152, 64, width/2, height/2 -20, width / 64.0, 0, false);
  opc.ledStrip(1216, 64, width/2, height/2 -30, width / 64.0, 0, false);
  opc.ledStrip(1280, 64, width/2, height/2 -40, width / 64.0, 0, false);
  opc.ledStrip(1344, 64, width/2, height/2 -50, width / 64.0, 0, false);
  opc.ledStrip(1408, 64, width/2, height/2 -60, width / 64.0, 0, false);
  opc.ledStrip(1472, 64, width/2, height/2 -70, width / 64.0, 0, false);
  opc.ledStrip(1536, 64, width/2, height/2 -80, width / 64.0, 0, false);
  opc.ledStrip(1600, 64, width/2, height/2 -90, width / 64.0, 0, false);
  opc.ledStrip(1664, 64, width/2, height/2 -100, width / 64.0, 0, false);
  opc.ledStrip(1728, 64, width/2, height/2 -110, width / 64.0, 0, false);
  opc.ledStrip(1792, 64, width/2, height/2 -120, width / 64.0, 0, false);
  opc.ledStrip(1856, 64, width/2, height/2 -130, width / 64.0, 0, false);
  opc.ledStrip(1920, 64, width/2, height/2 -140, width / 64.0, 0, false);
  opc.ledStrip(1984, 64, width/2, height/2 -150, width / 64.0, 0, false);

with this

for (int i = 0 ; i < 32 ; i++) {
   opc.ledStrip(i * 64, 64, width / 2, height / 2, 160 - 10 * i, width / 64.0, 0, false)
}

(i'd also add constants for width / 2, height / 2 and width / 64 fwiw, save calculating them all the time)

madmat99

that's great. But I'm still unsure where I put this in the capture sketch. Cheers

Mat

koogs

the opc stuff looks like it lives in setup(). it defines a mapping from a position in the processing window to the led strip.

so just put it in setup and it should be automatic.

(which is what jeremy said 2 days ago)

koogs

the "LED Mapping Example" does exactly this, sets up a mapping using new OPC, opc.ledStrip and then continually draws an image. that appears to be enough, you don't need to add anything opc specific to draw.

https://github.com/scanlime/fadecandy/blob/master/doc/processing_opc_client.md

the capture sketch will keep updating the image with video frames.

madmat99

hi guys, thanks so much for your help with this, got it working, I'm not sure why but it only works if i put OPC opc; above where it says setup. i know nothing about this program so don't know why that has to be there.... last question, do you know if i can import from a video capture device?

Thanks again.

Mat